As bassists, our main task is to lock in with the drums and hold down the groove for the entire band. That’s why we tend to gravitate towards pedals like compressors, overdrives, and fuzz pedals that help us add punch and grit to our sound.
But what if we told you there is an entire universe of sonic possibilities beyond these staples?
Modulation effects, often considered the domain of guitarists, can also be a secret weapon for bassists seeking to explore new tonal frontiers and add a new dimension to their playing.
Chorus, phaser, flanger, vibrato, and envelope filters are all effects that might conjure images of swirling guitar solos and psychedelic soundscapes. But don't let that fool you. When applied thoughtfully, modulation effects can transform your bass lines into dynamic, textured sounds that complement the mix in unexpected ways.
Whether you want to add subtle movement and depth to your sound or unleash a swirling vortex of sonic goodness, modulation effects have something to offer every bassist.
What is modulation? And how does it work?
Modulation effects are called such because they modulate or change the original audio signal in some way. This change can be to the pitch (like vibrato), the time (like chorus or flanging), or a combination of both.
Here's a simplified breakdown of how modulation effects work:
- Signal split: First the incoming audio signal is split into two identical copies.
- Modulation: One of the copies (the "wet" signal) is altered by an oscillator. This oscillator creates a cyclical change in pitch, time, or both. How much and in which way the wet signal is changed is what will give the character of the effect.
- Recombination: The altered "wet" signal is then mixed back with the original "dry" signal. The amount of wet signal blended in determines the intensity of the effect.
The controls on modulation pedals - which are typically rate, depth, and feedback - allow you to fine-tune the character and intensity of the modulation. Modifying these variables is what gives you a wide range of sonic possibilities, from subtle shimmer to extreme warble and swooshing.
All about Bass Chorus
What do Peter Hook, Geddy Lee, Duff McKagan, Simon Gallup, and Justin Chancellor have in common? Besides being legends in their own right, they all had a permanent spot in their rig for a chorus pedal.
NFTScrub - Own work, CC BY-SA 4.0, Link
Chorus pedals give the illusion that multiple versions of your bass are being played at the same time, making your bass sound huge, or it can give it an undulating and almost choppy characteristic that will transform your tone into a rhythmic pulse.
The effect works by first dividing your signal into two identical copies. One of these paths is then sent through a short delay line, typically ranging from 20 to 50 milliseconds. This delay is crucial in creating the illusion of multiple sound sources.
Next, the delayed signal is modulated in pitch by a low-frequency oscillator (LFO). The LFO creates a cyclical variation in the pitch, causing it to waiver slightly up and down. This is similar to how singers in a choir might not all be perfectly in tune, creating a chorus effect.
Finally, the original (dry) signal and the delayed, pitch-modulated (wet) signal are mixed together.
If Chorus is what’s missing from your tonal toolkit, here are some great options for you to consider:
JAM WATERFALL BASS CHORUS/VIBRATO PEDAL
The JAM Pedals Waterfall is a fully analog chorus and vibrato pedal that uses old-school BBD chips to help you create lush chorus sounds that go from subtle and chewy to close to the effect that you get from a Leslie rotating speaker. Also, you get a vibrato mode that can go from light pitch change to out-of-control weirdness. This is the perfect pedal if you’re after vintage chorus tones, but know that it can do much more.
AGUILAR CHORUSAURUS BASS PEDAL
The Aguilar Chorusaurus is Aguilar's take on the modern analog chorus pedal. Its layout features width, blend, rate, and intensity knobs that give you ample control over your chorus effect. These controls help you take it from adding a bit of harmonic interest to your tone with the blend low, all the way to a huge chorus sound that you’ve heard on classic songs.
Activate Phasers - Bass Style
A phaser pedal creates a swirling, whooshing effect that sweeps through your sound, adding movement and texture. This effect is achieved by splitting the incoming signal and applying phase shifting to one of the copies.
Phase shifting refers to changing the timing relationship between two waveforms. When two waveforms are "in phase," their peaks and troughs align perfectly. When they're "out of phase," their peaks and troughs don't align. Combining these in-phase and out-of-phase signals creates a series of notches and peaks in the frequency spectrum, resulting in the characteristic phaser sound.
Phasers are great if you’d like to add a bit of movement and texture to a simple bass line, or if you want to sound super swirly.
JAM RIPPLE BASS PHASER PEDAL
The Ripple Bass Phaser is JAM Pedal’s homage to the classic one-knob phaser, but with a unique redesign that works perfectly for Bass since it lets you keep much more of your low end than the original design.
It has one knob and it sounds great no matter where you turn it to. This is a great sounding 2 stage phaser that you may find yourself trying to fit into your setlist as much as possible.
AGUILAR GRAPE PHASER BASS PEDAL
The Grape Phaser is an all-analog 4-stage phaser that has two knobs to control rate and color. Rate lets you control the modulation speed while Color will manage the intensity of the effect.
Simple as it may seem, these two knobs allow you to cover a big range of phaser tones that go from subtle movement to an almost wah-like effect. The Grape Phaser is easy to use and is one of the modulation pedals that you can get a lot of mileage out of.
Turn up the funk with an Envelope Filter
An envelope filter (sometimes called an auto-wah) creates a distinctive "wah" sound that reacts to your playing dynamics. It emphasizes certain frequencies based on how hard you pluck or strike the strings and the settings you have on the pedal.
Unlike a wah pedal, which is controlled by a foot pedal, an envelope filter responds automatically to the characteristics of your playing. It's like having a wah pedal that moves on its own, following the intensity of your playing.
Used by players like Bootsy Collins, Flea, and Thundercat, the envelope filter can make your bass stand out by giving it a unique vocal quality that gives your bass line that little bit of extra funk that is needed.
Also worth mentioning is that besides the “Wah” effect, you can also use it as a filter of sorts, and get deep subsonic tones, or get a clanky upper-mid effect that can give your bass a tonal spectrum you couldn't reach otherwise.
Here are a couple of Envelope Filter recommendations we stock.
EBS BASSIQ BLUE LABEL ENVELOPE FILTER BASS PEDAL
The Bass IQ pedal has become one of the go-to choices for bassists looking to funk up their tone. The Swedish made pedal is built like a tank and is tuned in such a way that it’s super easy to get whatever tone you’re looking for. Getting some Bootsy-approved ‘Wha’s’ or some subtle warble is easy to reach with a turn of a couple of knobs.
AGUILAR FILTER TWIN ENVELOPE BASS PEDAL
The Filter Twin is an all-analog envelope filter that can give you an unexpectedly large range of sounds. With its four knobs (Blend, Threshold, Velocity Up, Velocity Down) you can get just about any kind of funky envelope tone you can think of and still retain your low-end thanks to the Blend knob. The Filter Twin is a great option if you’re looking to add some tasty vocal qualities to your tone and as an added bonus, it comes in a pedal-friendly form factor due to its small size and top-mounted input and output jacks.
From Subtle Shimmer to Seasick Swirl
Modulation pedals have the potential to unlock a whole new dimension of sonic expression for bassists. Whether it's the subtle shimmer of a chorus, the swirling sweep of a phaser, the vocal expressiveness of an envelope filter, or the hypnotic pulse of a vibrato, these effects can transform your bass lines from ordinary to extraordinary.
If you’re not sure which modulation pedal is for you, feel free to give us a call or shoot us an email. We’re big fans of bass pedals here at Fat Bass Tone and we’re sure we can help you find the perfect one for your board.